Designing RESTful APIs That Don't Suck

Bad API design creates technical debt that lasts years. Here's what we learned.

Be Consistent

Pick a pattern and stick to it:

• Plural nouns for collections: /items, not /item
• Nested resources: /orders/123/items
• Standard HTTP methods: GET, POST, PUT, DELETE

Version Early

We started at /api/v1/. When we need breaking changes, we'll add /api/v2/ and maintain both.

Validate Input

Every request. Every field. Return clear error messages with field-level details.

{
  "error": "Validation failed",
  "details": {
    "email": "Invalid email format",
    "price": "Must be greater than 0"
  }
}

Paginate Everything

Lists grow. Don't return 10,000 items. Use cursor-based pagination for consistency.

Document It

We use Swagger/OpenAPI. Auto-generated docs from code. Stays up to date automatically.

The Payoff

Good API design makes integration painless. Bad design makes it hell.

Choose wisely.